Climate change is a major problem for today's society, which has a huge impact on water safety issues. Recent IPCC scenarios show that sea level rises of 1m by 2100 and 2m beyond 2200 should be seriously considered. Several scenarios show an increase in river discharge of between 10 and 20 percent of the Rhine generated by extreme precipitation by the year 2050. The combination of the sea level rise and the increase in river discharge has consequences for the flood risk in the Netherlands. The area where most people live, about 3,5 million, and where most of the gross national product, around 65 percent, is earned is the area of dikering 14. This thesis determines how the flood risk changes for future climate change scenarios, considering a sea level rise up to 2m and an associated increase in river discharge. One base case scenario with the current situation and four future scenarios with a sea level rise up to 2m with increments of 0,5m were evaluated. The river dikes along the trajectories of the Hollandse Ijssel, Nieuwe Maas and Nieuwe Waterweg and the dunes between Hoek van Holland and Ijmuiden were assessed and the consequences of flooding due to a dune or dike breach were investigated for all scenarios.

Flood risk is determined by the probability of failure of a flood defence and the consequences in case of a flood, which are expressed in economic damage, casualties and affected persons. The influence of climate change on the probability of flooding of 8 river dike profiles was investigated by assessing the failure mechanism overtopping and overflow, using a relationship between height shortage and the probability of failure. The safety of the dunes was evaluated using the Duros-plus model, with which dune erosion calculations were made. The results show that climate change has a big impact on the probability of failure, which is highest for the trajectory along the Hollandse Ijssel with a probability of failure of 1/370.000 per year in the current situation and 1/170 per year in the scenario involving a 2 m sea level rise. Although the failure probabilities of the dunes are very low in the current situation, the influence of sea level rise is shown for the dunes with failure probabilities that are a factor of 2000-3000 higher in a scenario with 2m sea level rise compared to the base case scenario.

For determining the consequences, both existing flood scenarios for the river side and new flood scenarios for the seaside were used. The new flood scenarios show the effect of sea level rise on the increased flood extent caused by a dune breach for each scenario. The potential economic damage, which is determined by the flood depth, damage curves and the land use map, is highest for a dike failure along the Hollandse Ijssel, as the highest flood depths are reached in these deep polders. The highest number of casualties, 7900, determined by the mortality rates based on flood depth, flow velocity, rise rate and evacuation factor, are expected in case of a dike failure along the Nieuwe Maas, as the densely populated cities of Rotterdam and Schiedam are flooded. By assigning monetary values for casualties and affected persons, the total damage is determined, to which the damages resulting from casualties and affected persons contribute most.

After determining the costs of several reinforcement projects, these costs and the potential total damage were used as input in a cost-benefit analysis, where economic optimums were determined expressed in a probability of failure and associated investment costs. The conclusion is that it is economically efficient to reinforce all flood defences except for the trajectory along the Nieuwe Waterweg in case of a scenario corresponding to 2m sea level rise. It was also examined whether the economic optimums met the requirement that everyone should have a maximum risk of dying due to a flood of 10^-5 per year. A total length of 40,5 km river dikes and 63,5 km of dunes will need to be reinforced, for which the costs of reinforcing the river dikes are significantly higher per km than for the dunes, approximately 20 and 3,8 million euros/km respectively. The total estimated costs determined in this study are around 1 billion euros for a 2m sea level rise scenario, but these costs for keeping the area safe will be a factor of 2-3 higher, as the method used for determining the costs of river dikes leads to an underestimation compared to the costs in reality. In addition, hydraulic structures and future subsidence are not included, which will also lead to higher total costs. With these investments the flood risk will remain acceptable and the river dikes and dunes will continue to offer sufficient protection against floods with a total potential damage of 230 billion euros, consisting of 70 billion euros in economic damage, 20.000 casualties and 2,5 million affected persons.

Economic risk due to a potential flood event is determined by combining the estimated damages and the probability of failure for many scenarios. In recent research of the IPCC (Intergovernmental Panel on Climate Change) it was stated that the sea level will rise more than expected due to climate change . This could influence the flood risk in coastal areas including the Netherlands. In this thesis the influences of the sea level rise on the flood risk for dijkring 14 will be evaluated. Dijkring 14 is located in the coastal area of the Netherlands and contains Rotterdam, the Hague and parts of Utrecht and Amsterdam. It has 3.500.000 inhabitants, consists of an area of 224.000 acres and has the largest potential economic damages. The average elevation of the dijkring is one meter below NAP. The coastal area is protected by hydraulic structures and dunes which are both subjected to an increase of probability of failure due to sea level rise. In this thesis it is assessed if the protection of the coastal area by means of dunes is possible in case of an extreme sea level rise future scenario. With an hydrodynamic flood simulation future flood events dominated by extreme sea level rise are simulated. The hydrodynamic flood simulation is executed by Delft3D Flow FM. In D-Flow FM the unsteady shallow water equations are solved based on the Navier Stokes equations. It solves in 2 dimensions with an average water depth per grid cell. This results in accurate water flow over land. The hydrodynamic flood simulation is verified by comparing the result of the current scenario with the the widely accepted VNK2 model. The validation is executed based on a visual comparison, a inundation depth comparison and a comparison of the estimated damages. This assessment was done for three different breach locations and resulted in a reliable hydrodynamic flood simulation. To estimate the damages that occur during a flood event that is simulated by the hydrodynamic simulation, the Global Flood Risk Tool was used. This tool combined the inundation depth, the land use map and the damage curves and created a damage map. This map represented the estimated damage per area which resulted in a total estimated damage per flood event. Flood risk is determined by a combination of estimated damages and probability of failure. With the hydrodynamic simulation and the Global Flood Risk Tool, damages were estimated for three breach locations and five different future extreme sea level rise flood scenarios. This resulted in a damage estimation for sea level rise scenarios up to two meter rise. The probability of failure is estimated by means of the height that is needed to decrease the probability of failure by a factor ten. Economic optimisation was used to determine the economically optimal probability of failure for each of the scenarios. With the economic optimisation, the cost and benefits of the investments needed to increase the the probability of failure are calculated. These optimal probability of failures were compared to the minimal required probabilities of the 'waterwet' of the Netherlands to determine if the investment is economically acceptable. For two of the three locations it became clear that investing in strengthening the dunes of the coastal area of dijkring 14 is economically acceptable. The third location resulted in a slightly smaller optimal probability of failure. When estimating for the whole coastal area of dijkring 14, it becomes clear the defending the dijkring against flood risk by use of the dunes is possible in future extreme sea level rise scenarios.

Inland waterway transport (IWT) is one of the three main modalities for inland transport of dry, liquid and containerized cargo. As IWT performs well on cost-competitiveness, environmental friendliness, and congestion-related issues, authorities strive to shift freight transport from road to water. Inland waterway connections, however, are vulnerable to the growing impact of climate change. A combination of higher temperatures and more extreme seasonal differences in precipitation is expected to increasingly impact river discharge in the future. In summer, this will result in low water events happening more frequent and more intense. The effects of climate change on IWT could result in a reduced annual transport capacity, thereby weakening the reputation of IWT and increasing the costs of cargo shipment. The objective of this research is to provide more insight into the consequences of climate change-induced low discharges on the performance of IWT and to assist in making justified adaptation decisions. During this research, an IWT performance model has been developed that is capable of studying the capacity and vulnerability of the inland waterway system to low water depths, and simultaneously can be used to propose measures to strengthen the position of IWT. To assess the quality of the logistic simulations, the model has successfully been subjected to a number of validity tests. Consequently, the model was calibrated on two parameters that have a high uncertainty and a significant impact on the simulation. After calibration, the model shows correlation coefficients of r=0.794 and r=0.921 so that it can be concluded that the results of the IWT performance model are relatively accurate with reality. Daily projections of the water depth on the Rhine are obtained by extrapolation of the representative, dry year 1976 with two climate scenarios to the year 2050. The water depths encountered have been compared to the base scenario. To put into perspective these impacts, a model run for the reference scenario of 2018 has been incorporated in the comparison. It follows from this thesis that low discharges, in combination with navigational restrictions, could cause substantial losses for the IWT in 2050 in terms of transported cargo and transport costs. Following from literature, the accurate modelling of IWT should include various local effects that follow from regulations, fleet composition or waterway characteristics. This research is the first study on the impact of low water depths on the IWT performance that does not take the load factor as the only variable but that includes other network parameters as the active fleet size and the number of trips to provide a comprehensive picture of the IWT performance in periods of low discharge.